This thought might or might not be shared among the Leafs scouts and management personnel... hell it might be Marner, not Strome, in the example. Fact is that after the top 2, there's little ways to determine who the BPA will be except for conjecture and preconceived biases.
Both Marner and Strome look to be world class players and the thinking among scouts is that Hanifin, Werenski and Provorov are interchangeable this year. It's a real crap shoot if the guy we get at #4 will be the definite best of the bunch. Personally, I just don't want us to pick this year's Sam Gagner and I'm kind of wary this year. Just look at how much the top forwards' production numbers are propped up playing alongside legitimate talent. There's also the fact that guys face secondary pairings more often than say, oh I don't know, Lawson freaking Crouse.
Crouse, Barzal, Rantanen, Connor each have legitimate reasons why they could jump up and be drafted within the top-10.
Unsurprisingly, at the end of the day, the scouts will be able to assess who to pick and who not to pick. They do interviews and learn about the kids habits and personalities and these traits are equally necessary for proper player development.